JP5487780B2 - Lens barrel and camera - Google Patents

Description

  The present invention relates to a lens barrel and a camera including the same.

  Conventionally, there is a camera that bends subject light incident along a first optical axis in a second optical axis direction orthogonal to the first optical axis. In such a bendable camera, a plurality of lens groups are arranged along the second optical axis, and two lens groups sandwiching one lens group (for example, a shake correction lens) are respectively connected to individual actuators. (See, for example, Patent Document 1).

JP 2007-199404 A

  However, when the number of actuators provided in one camera increases, it is difficult to reduce the size of the camera.

  An object of the present invention is to provide a lens barrel and a camera that can be miniaturized.

The present invention solves the above problems by the following means.
According to the first aspect of the present invention, in the lens barrel that bends the first optical axis to the second optical axis orthogonal to the first optical axis by the reflecting member, the second optical axis from the incident side. The first lens group, the second lens group, the third lens group, and the fourth lens group, which are sequentially disposed along the first lens group, and the first lens group and the third lens group are moved along the second optical axis. A first actuator to move, a second actuator to move the fourth lens group along the second optical axis, and a third actuator to move the second lens group in a plane perpendicular to the second optical axis. An actuator, a first drive shaft disposed in parallel with the second optical axis and rotated by driving the first actuator, and disposed in parallel with the second optical axis, and driven by the second actuator. The second drive shaft to be rotated and the first lens group are fixed. A first lens group frame having an engaging portion to move along the first drive shaft as well as, a third lens group frame to affix said third lens group, together with fixing the fourth lens group wherein A fourth lens group frame having an engaging portion that moves along the second drive axis, wherein the first drive axis and the second drive axis are the first optical axis and the second optical axis. Are partially overlapped in a direction perpendicular to the second optical axis, and the first drive axis is more than the second optical axis from the second drive axis. positioned away from the third lens group frame may have a through portion in which the second drive shaft extends, along the first drive shaft spaced apart from the second optical axis from the through portion A lens barrel characterized by having an engaging portion that moves in a moving manner .
The invention according to claim 2 is the lens barrel according to claim 1, wherein the first lens group frame and the third lens group frame move along the same first rectilinear guide shaft, The first lens group frame and the third lens group frame are lens barrels characterized in that rotation about the optical axis is restricted by the same rotation stop shaft.
The invention according to claim 3 is the lens barrel according to claim 2, wherein the first rectilinear guide shaft and the first drive shaft are arranged at an equal distance from the optical axis. This is a featured lens barrel.
The invention according to claim 4 is the lens barrel according to claim 3, wherein rotation axes of the first actuator and the second actuator are parallel to the second optical axis, and The lens barrel is disposed on the same side of the outer periphery, and the first drive shaft is disposed between the first actuator and the second actuator in parallel with the second optical axis. is there.
The invention according to claim 5 is the lens barrel according to any one of claims 1 to 4, comprising a second rectilinear guide shaft for guiding rectilinear advance of the fourth lens group frame, The lens barrel characterized in that the second drive shaft and the second rectilinear guide shaft are arranged at an equal distance from the optical axis.
The invention according to claim 6 is the lens barrel according to any one of claims 1 to 5, wherein the first lens group frame, the third lens group frame, and the fourth lens group frame are: The lens barrel is characterized in that rotation about the optical axis is restricted by the same rotation stop shaft.
A seventh aspect of the present invention is a camera including the lens barrel according to any one of the first to sixth aspects.

  ADVANTAGE OF THE INVENTION According to this invention, the lens barrel and camera which can be reduced in size can be provided.

1 is an external perspective view conceptually showing a camera including a lens barrel that is an embodiment of the present invention. It is sectional drawing of the lens barrel equivalent to the AA arrow in FIG. It is sectional drawing of the lens-barrel equivalent to the BB arrow in FIG. It is a perspective view which extracts and shows the movement drive structure of the lens group in a lens barrel. It is the perspective view which looked at the inside of a frame from the back side. It is CC sectional drawing of FIG. It is explanatory drawing which shows the arrangement positional relationship of a zoom guide bar, a zoom drive shaft, a focus guide bar, and a focus drive shaft with respect to the 2nd optical axis.

  Embodiments of the present invention will be described below with reference to the drawings. Each drawing described below is provided with an XYZ orthogonal coordinate system for ease of explanation and understanding. In this coordinate system, when the photographer shoots a horizontally long image with the optical axis A horizontal, the direction toward the left as viewed from the photographer at the position of the camera (hereinafter referred to as the positive position) is the X plus direction and the positive position. The direction toward the upper side is the Y plus direction, and the direction toward the subject at the normal position is the Z plus direction. The Z-axis plus direction is also called the front side, and the Z-axis minus direction is also called the back side. Further, the Y plus direction is also called the upper side, and the Y minus direction is also called the lower side.

  FIG. 1 is an external perspective view conceptually showing a camera 1 including a lens barrel 10 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the lens barrel 10 corresponding to the AA arrow in FIG. FIG. 3 is a cross-sectional view of the lens barrel 10 corresponding to the arrow BB in FIG.

The camera 1 is a so-called digital camera that records a subject image formed by an optical system as electrical image data. The present invention is not limited to a digital camera, and can be applied to, for example, a still camera using a film.
The camera 1 includes an imaging optical system 20, a shutter unit 30, a sensor unit 40, and a display device 50. A release button 60 is provided on the upper surface of the camera 1.

The imaging optical system 20 and the shutter unit 30 are provided on the frame 11 and constitute the lens barrel 10.
The frame 11 has a hollow rectangular parallelepiped-like schematic shape, and is substantially open to the back side except for the arrangement site of the bending introduction lens group 21 in the imaging optical system 20 described later.
The open back portion of the frame 11 is closed by the cover 12. Further, the outside of the frame 11 is covered with the outer casing 13, and the display device 50 and the release button 60 are provided on the outer casing 13.

The imaging optical system 20 includes a bending introduction lens group 21, a first lens group L1, a second lens group L2, a third lens group L3, and a fourth lens group L4.
The bending introduction lens group 21 includes an objective lens 21A, a prism 21P, and an emission lens 21B, and is fixed to the frame body 11. The prism 21P is a right-angle prism, and is disposed so as to reflect and bend the subject light incident on the objective lens 21A from the front side (Z-axis plus side) by 90 ° to the Y-axis minus side. Thereby, the bending introduction lens group 21 bends the subject light incident on the objective lens 21A from the plus side in the Z-axis by 90 ° in the Y-axis minus direction by the prism 21P, and the bent subject light is emitted from the exit lens 21B. To do. The optical axis along the Z-axis on the incident side is the first optical axis OA1, and the optical axis along the Y-axis after bending is the second optical axis OA2.

The first lens group L1, the second lens group L2, the third lens group L3, and the fourth lens group L4 are disposed along the second optical axis OA2 (in the Y-axis direction).
The first lens group L1 and the third lens group L3 constitute a zooming lens that changes the combined focal length of the imaging optical system 20.
The first lens group L1 is attached to the first lens group frame 101, and the third lens group L3 is attached to the third lens group frame 103. The first lens group frame 101 and the third lens group frame 103 can be disposed inside the frame body 11 from the open back side of the frame body 11 during assembly.

  The first lens group frame 101 and the third lens group frame 103 (that is, the first lens group L1 and the third lens group L3) can be driven to move in the Y-axis direction (along the second optical axis OA2). It is provided on the body 11. The focal length of the imaging optical system 20 is changed by the movement of the first lens unit L1 and the third lens unit L3 in the direction of the second optical axis OA2. The movement drive structure of the first lens unit L1 and the third lens unit L3 will be described in detail later.

The second lens group L2 is a shake correction lens group, and is attached to the movable frame 201 in the shake correction mechanism unit 200.
The shake correction mechanism unit 200 includes a movable frame 201 that supports the second lens group L2 and a fixed frame 202 that is fixed to the frame body 11. A ball 203 and an actuator 204 are disposed between the movable frame 201 and the fixed frame 202.

The ball 203 supports the movable frame 201 so as to be movable in a plane perpendicular to the second optical axis OA2 while defining a distance between the movable frame 201 and the fixed frame 202.
The actuator 204 drives and moves the movable frame 201 in a plane perpendicular to the second optical axis OA2 with respect to the fixed frame 202.
Thereby, the movable frame 201 is smoothly moved in a plane perpendicular to the second optical axis OA <b> 2 with respect to the fixed frame 202 by rolling of the ball 203 by driving of the actuator 204.

  Then, the shake correction mechanism unit 200 moves the movable frame 201 (second lens group L2) so as to cancel the movement of the subject image on the imaging surface of the imaging device 41, which will be described later, according to the movement of the camera 1 due to camera shake or the like. Move in a plane perpendicular to the second optical axis OA2. This acts to reduce image blurring of the subject image on the imaging surface of the image sensor 41 due to vibration such as camera shake.

As described above, the second lens group L2 (blur correction mechanism unit 200), which is the blur correction lens group, is disposed between the first lens group L1 and the third lens group L3, which are zooming lenses. A large blur correction amount can be obtained with a small movement amount of the lens unit L2. Thereby, it is possible to suppress the deterioration of the optical performance due to the blur correction.
The blur correction mechanism unit 200 is also arranged in the frame 11 from the open back side of the frame 11 during assembly, as in the first lens group frame 101 and the third lens group frame 103 described above. To get.
Further, the shake correction mechanism unit 200 is formed with a through hole through which a zoom guide bar 121 (not shown in FIG. 3, see FIG. 4) and a rotation stop guide bar 122 in a zoom guide mechanism 120 described later is disposed. Yes.

The fourth lens unit L4 is a focusing lens that adjusts the focus of the subject image on the imaging surface of the imaging element 41. The fourth lens group L4 is attached to the fourth lens group frame 104.
The fourth lens group frame 104 (fourth lens group L4) is provided on the frame body 11 so as to be movable in the Y-axis direction (along the second optical axis OA2). The focal position of the imaging optical system 20 is changed by the movement of the fourth lens unit L4 in the direction of the second optical axis OA2. The moving structure of the fourth lens unit L4 will be described in detail later.
The fourth lens group frame 104 can be disposed inside the frame body 11 from the open back side of the frame body 11 in the same manner as the first lens group frame 101 and the third lens group frame 103 during assembly. It is like that.

  The shutter unit 30 is fixed to the frame 11 on the incident side of the second lens unit L2 in the imaging optical system 20 (that is, the incident side of the shake correction mechanism unit 200). The shutter unit 30 can be disposed inside the frame body 11 from the open back side of the frame body 11.

The sensor unit 40 is fixed to the lower surface (the surface on the negative side of the Y axis) of the frame body 11. The sensor unit 40 includes an image sensor 41, a low-pass filter 42, and the like.
The image sensor 41 is a photoelectric conversion element such as a CCD, for example, and receives subject light and converts (images) it into an electrical image signal.

  The low-pass filter 42 is formed of a quartz birefringent plate or the like, and is disposed on the front surface (incident side) of the image sensor 41. The low-pass filter 42 removes high-frequency components of subject light incident on the image sensor from the fourth lens group L4, and prevents the occurrence of interference fringes (moire) in the subject image.

  The display device 50 is configured by a liquid crystal display or the like, and is disposed on the back side of the exterior housing 13. The display device 50 displays an image captured by the image sensor 41, a menu screen, and the like.

  In the camera 1, the imaging optical system 20 forms an image of the subject image light on the sensor unit 40 (the light receiving surface of the imaging device 41), and the sensor unit 40 converts the release signal 60 into an electric signal when the photographer presses the release button 60. The converted image information of the subject is recorded (photographed) in a storage device (not shown). The display device 50 displays real-time subject images (through images) captured by the sensor unit 40 and captured images recorded in the storage device. All the operation control in the camera 1 including the photographing is performed by a control device (not shown).

Next, referring to FIGS. 4 to 7 in addition to FIGS. 1 to 3 described above, the first lens unit L1 and the third lens unit L3 in the lens barrel 10, which is a characteristic part of the present embodiment, are described. The movement drive structure and the movement drive structure of the fourth lens unit L4 will be described in detail.
FIG. 4 is a perspective view showing the movement driving structure of the lens groups L1 to L4 in the lens barrel 10, and the viewpoint substantially corresponds to FIG. FIG. 5 is a perspective view of the inside of the frame body 11 as viewed from the back side. FIG. 5 shows a state in which the blur correction mechanism unit 200 including the bending introduction lens group 21 and the second lens group L2 and the sensor unit 40 are not attached. 6 is a cross-sectional view taken along the line CC of FIG. FIG. 7 is an explanatory diagram showing the positional relationship between the zoom guide bar 121, the zoom drive shaft 130, the focus guide bar 421, and the focus drive shaft 430 with respect to the second optical axis OA2.

As described above, the first lens unit L1 and the third lens unit L3 constitute a zooming lens. The first lens group L1 is attached to the first lens group frame 101, and the third lens group L3 is attached to the third lens group frame 103.
The first lens group frame 101 (first lens group L1) and the third lens group frame 103 (third lens group L3) are driven to move by the zoom drive mechanism 100.
Although the first lens group frame 101 and the third lens group frame 103 are partially different, the basic shapes are substantially the same. Hereinafter, the zoom lens group frame 110 will be described unless otherwise distinguished. To do.

The zoom drive mechanism 100 includes a zoom guide mechanism 120, a zoom drive shaft 130, and a zoom motor 140.
The zoom guide mechanism 120 includes a zoom guide bar 121 (not shown in FIG. 3, see FIGS. 4 and 5) and a rotation stop guide bar 122. The zoom guide bar 121 and the rotation stop guide bar 122 each have a length over the entire vertical direction (Y-axis direction) of the frame body 11.

The zoom guide bar 121 has a round shaft shape with a predetermined diameter, and is provided on the X-axis plus side of the second optical axis OA2 so that both ends are supported by the upper and lower walls of the frame 11 and parallel to the second optical axis OA2. It has been.
The rotation stop guide bar 122 has a round shaft shape with a predetermined diameter, and is supported on the X-axis minus side of the second optical axis OA2 and both ends are supported by the upper and lower walls of the frame 11, and parallel to the second optical axis OA2. Is provided.

  The zoom drive shaft 130 is a so-called cylindrical cam in which cam grooves (a first cam groove 131 and a third cam groove 132) are spirally formed on the outer periphery of a shaft having a predetermined diameter. The zoom drive shaft 130 is rotatably disposed on the X axis plus side of the second optical axis OA2 with its central axis parallel to the second optical axis OA2. The lower end (end on the Y axis minus side) of the zoom drive shaft 130 is rotatably supported by a bearing portion 11 </ b> A formed on the lower wall of the frame body 11. A driven gear 152 is provided at the end of the zoom drive shaft 130 on the Y axis plus side. The distal end portion of the zoom drive shaft 130 protruding from the driven gear 152 is rotatably supported by a bearing 142 provided on a mounting flange 141 of the zoom motor 140 described later.

Cam grooves (first cam groove 131 and third cam groove 132) in the zoom drive shaft 130 are formed in the vicinity of both ends of the zoom drive shaft 130, respectively.
The first cam groove 131 on the upper end side (Y-axis plus side) is formed in a left-handed manner (screwed counterclockwise) when viewed from the upper end side. On the other hand, the third cam groove 132 on the lower end side (Y axis minus side) is formed in a clockwise direction (screwed clockwise).
A cam follower 114 (described later) provided in the first lens group frame 101 is fitted in the first cam groove 131. Further, the cam follower 114 provided in the third lens group frame 103 is fitted in the third cam groove 132.

Thereby, the zoom drive shaft 130 is engaged with the first lens group frame 101 (first lens group L1) and the third lens group frame 103 (third lens group L3) by the rotation thereof. It is driven to move according to the displacement in the axial direction of the cam grooves (first cam groove 131, third cam groove 132). That is, the first lens group frame 101 (first lens group L1) and the third lens group frame 103 (third lens group L3) are moved and driven by the rotation of one zoom drive shaft 130, respectively. .
The moving direction and moving amount of the first lens group frame 101 (first lens group L1) and the third lens group frame 103 (third lens group L3) can be set independently.

  In this embodiment, when the zoom drive shaft 130 rotates clockwise as viewed from above, the first lens group frame 101 (first lens group L1) moves downward (Y-axis minus side), and the third The lens group frame 103 (third lens group L3) moves toward the upper side (Y-axis plus side). That is, the first lens unit L1 and the third lens unit L3 are moved close to each other.

  Here, the zoom guide bar 121 and the zoom drive shaft 130 are disposed in the zoom guide mechanism 120 in the X-axis plus direction with respect to the second optical axis OA2 (the centers of the first and third lens units L1 and L3). The distance is set to be approximately equal to and is substantially superposed in the Z-axis direction. Further, as shown in FIG. 7A, the distance from the second optical axis OA2 (centers of the first and third lens groups L1 and L3) to the axial center of the zoom guide bar 121: d1, and the second optical axis The distance d2 from OA2 to the center of the zoom drive shaft 130 is set equal. With this setting, the distance between the zoom guide bar 121 and the zoom drive shaft 130 can be minimized, so that drive efficiency is good.

The zoom motor 140 is mounted via a mounting flange 141 on the outer surface of the upper wall of the X-axis plus side end of the frame body 11, which is substantially above the zoom drive shaft 130. The zoom motor 140 is provided with its rotation axis parallel to the second optical axis OA2.
The rotation shaft of the zoom motor 140 protrudes inside the frame body 11, and a drive gear 151 is attached to this protruding portion.

  A mounting flange 141 in the zoom motor 140 is integrally fixed to the front surface portion (the side from which the rotation shaft protrudes) of the zoom motor 140. The mounting flange 141 is fastened to the frame body 11 with screws so that the zoom motor 140 is fixed to the frame body 11. As described above, the mounting flange 141 includes the bearing 142 that rotatably supports the upper end (Y axis plus side) of the zoom drive shaft 130.

  The mounting portion of the mounting flange 141 in the frame 11 is opened and cut away on the back side, and this open portion is blocked by the mounting flange 141. With such a configuration, the zoom drive shaft 130 can be assembled by being inserted into the inside of the frame body 11 from the open portion on the back side of the frame body 11.

  The drive gear 151 attached to the rotation shaft of the zoom motor 140 and the driven gear 152 attached to the zoom drive shaft 130 generate rotational force via an idle gear 153 (not shown in FIG. 3; see FIG. 5). It is connected so that it can be transmitted. Thereby, the zoom drive shaft 130 is rotationally driven by the rotation of the zoom motor 140.

  The zoom lens group frame 110 (the first lens group frame 101 and the third lens group frame 103) is slidably fitted to the zoom guide bar 121 in the zoom guide mechanism 120 with a predetermined tolerance, as shown in FIG. 4 (see FIG. 4 and FIG. 6), and a guide slit 112 that is slidably fitted to the rotation stop guide bar 122 of the zoom guide mechanism 120 with a predetermined tolerance.

The guide hole 111 is formed by penetrating a guide portion 113 formed at the end on the plus side of the X axis in the zoom lens group frame 110 in the Y axis direction. The guide portion 113 has a substantially rectangular cross-sectional shape and is formed longer than the thickness of the zoom lens group frame 110 in the Y-axis direction.
The guide slit 112 extends in the shape of a long hole along the direction extending the line connecting the axis of the zoom guide bar 121 and the axis of the rotation stop guide bar 122, and extends toward the end of the zoom lens group frame 110. It is open.

  In the zoom lens group frame 110, the guide hole 111 is fitted to the zoom guide bar 121, and the guide slit 112 is fitted to the rotation stop guide bar 122, and is attached to the zoom guide mechanism 120. In the zoom lens group frame 110, the circumferential position around the zoom guide bar 121 is defined by the rotation stop guide bar 122, and the second optical axis OA2 with the accuracy defined by the fitting with the zoom guide bar 121. It is supported to move in parallel.

In addition, the zoom lens group frame 110 includes a cam follower 114 that fits into the cam grooves (the first cam groove 131 and the third cam groove 132) in the zoom drive shaft 130.
The cam follower 114 is provided in a guide portion 113 that protrudes on the X axis plus side of the zoom lens group frame 110.

  The cam follower 114 has an axial shape with a predetermined diameter, and has a tapered tip. The cam follower 114 passes through the guide portion 113 from the substantially front side to the back side in the substantially Z-axis direction, and is provided with a rear end that is pressed and urged by the pressing spring 115. The central axis of the cam follower 114 is directed toward the center of the zoom drive shaft 130.

As described above, the cam follower 114 provided in the zoom lens group frame 110 (the first lens group frame 101 and the third lens group frame 103) is the cam groove (first cam groove 131) of the zoom drive shaft 130 as described above. , The third cam groove 132).
That is, the cam follower 114 of the first lens group frame 101 is fitted into the first cam groove 131 in the zoom drive shaft 130, and the cam follower 114 of the third lens group frame 103 is fitted into the third cam groove 132 in the zoom drive shaft 130. doing.

  As a result, the first lens group frame 101 (first lens group L1) and the third lens group frame 103 (third lens group L3) are cams to which the cam followers 114 are fitted by the rotation of the zoom drive shaft 130, respectively. It is driven to move according to the axial displacement of the grooves (first cam groove 131, third cam groove 132).

  In the zoom drive mechanism 100 configured as described above, the zoom drive shaft 130 is rotationally driven by the zoom motor 140. Due to the rotation of the zoom drive shaft 130, the first lens group frame 101 (first lens group L1) and the third lens group frame 103 (third lens group L3) are guided by the zoom guide mechanism 120, respectively. It moves along the optical axis OA2. As a result, the focal length of the imaging optical system changes. The rotation control of the zoom motor 140 is performed by a control unit (not shown) of the camera 1.

According to such a zoom drive mechanism 100, the two lens groups of the first lens group L1 and the third lens group L3 are interlocked by one zoom drive shaft 130 that is rotationally driven by one zoom motor 140. It can be moved and driven. Thereby, the 1st lens group L1 and the 3rd lens group L3 can be interlocked with high precision.
Further, since the two lens groups are moved and guided by one zoom guide mechanism 120 (the zoom guide bar 121 and the rotation stop guide bar 122), it can be configured with high accuracy.

  Furthermore, after the first lens group frame 101 and the third lens group frame 103 are arranged inside the frame body 11 from the open back side, the zoom guide bar 121 is inserted from above (or below) the frame body 11. By using the assembly process to arrange, assembly can be performed very easily.

Next, the movement drive structure of the fourth lens unit L4 will be described in detail.
The fourth lens unit L1 constitutes a focusing lens as described above. The fourth lens group L1 is attached to the fourth lens group frame 104. The fourth lens group L4 is driven to move by the focus driving mechanism 400.
The focus drive mechanism 400 includes a focus guide mechanism 420, a focus drive shaft 430, and a focus motor 440.

  The focus guide mechanism 420 includes a focus guide bar 421 (not shown in FIG. 3; see FIG. 5) and a rotation stop guide bar 122 in the zoom drive mechanism 100 described above. That is, the focus guide mechanism 420 also uses the rotation stop guide bar 122 in the zoom guide mechanism 120 of the zoom drive mechanism 100.

  The focus guide bar 421 has a round shaft shape with a predetermined diameter, and is provided on the X-axis plus side of the second optical axis OA2, with the lower end supported by the lower wall of the frame 11 and in parallel with the second optical axis OA2. ing. That is, the focus guide bar 421 is provided in a cantilever manner. The length of the focus guide bar 421 is set to a movement range required for the focusing operation of the fourth lens unit L4. Further, the position of the focus guide bar 421 in the X-axis direction is closer to the second optical axis OA2 than the zoom guide bar 121 in the zoom guide mechanism 120 of the zoom drive mechanism 100.

  The focus drive shaft 430 is a shaft-shaped feed screw (screw) having a predetermined diameter and a predetermined length. The focus drive shaft 430 is rotatably supported on the lower wall surface of the frame 11 at its end. That is, the focus drive shaft 430 is also cantilevered like the focus guide bar 421.

The length of the focus drive shaft 430 is set to a moving range required for the focusing operation of the fourth lens unit L4. As shown in FIG. 3, the focus drive shaft 430 interferes with the third lens group frame 103 that supports the third lens group L3 depending on conditions. For this reason, as shown in FIG. 6, a through hole 103 </ b> A through which the focus drive shaft 430 can pass is formed at a position corresponding to the focus drive shaft 430 of the third lens group frame 103. Furthermore, a through-hole 103B through which the focus guide bar 421 can pass is formed at a position corresponding to the focus guide bar 421 of the third lens group frame 103.
A driven gear 452 is attached to the tip of the focus drive shaft 430 that projects downward from the wall surface of the frame 11.

The focus motor 440 is mounted via a mounting flange 441 on the outer surface of the lower wall of the X-axis plus side end of the frame 11, which is substantially below the zoom drive shaft 130. That is, the focus motor 440 is disposed on the same side of the frame body 11 as the zoom motor 140 (X-axis plus side) so as to sandwich the zoom drive shaft 130 substantially vertically with the zoom motor 140.
The focus motor 440 is provided with its rotation axis parallel to the second optical axis OA2. The rotation shaft of the focus motor 440 protrudes inside the frame 11, and a drive gear 451 is attached to this protrusion as shown in FIG. 4.

  As shown in FIG. 4, the drive gear 451 attached to the rotation shaft of the focus motor 440 is connected to the driven gear 452 attached to the focus drive shaft 430 so as to be able to transmit the rotational force via the gear set 453. Yes. Thereby, the focus drive shaft 430 is rotationally driven by the rotation of the focus motor 440.

  The fourth lens group frame 104 has a guide hole 411 (not shown in FIG. 3; see FIG. 5) that is slidably fitted to the focus guide bar 421 in the focus guide mechanism 420 with a predetermined tolerance, and a rotation stop guide bar. A guide slit 412 that is slidably fitted to 122 with a predetermined tolerance and a drive female screw 413 that is screwed to the focus drive shaft 430 are provided.

  In the fourth lens group frame 104, the guide hole 411 is fitted to the focus guide bar 421, the guide slit 412 is fitted to the rotation stop guide bar 122, and the focus drive shaft 430 is screwed to the drive female screw 413. And supported by the focus guide mechanism 420.

  With this configuration, the fourth lens group frame 104 moves in a direction parallel to the second optical axis OA2 along the focus guide bar 421 and the rotation stop guide bar 122 by the rotation of the focus drive shaft 430. During this movement, accuracy in the movement direction is defined by fitting with the focus guide bar 421, and a circumferential position around the focus guide bar 421 is defined by the rotation stop guide bar 122.

  Here, the disposition positions of the focus guide bar 421 and the focus drive shaft 430 in the focus guide mechanism 420 are set to a distance substantially equal to the X-axis plus direction with respect to the second optical axis OA2, and substantially overlap in the Z-axis direction. doing. Further, as shown in FIG. 7B, the distance from the second optical axis OA2 to the axis center of the focus guide bar 421: d3, and the distance from the second optical axis OA2 to the axis center of the focus drive shaft 430: d4. Are set equal. With this setting, the distance between the focus guide bar 421 and the focus drive shaft 430 can be minimized, so that drive efficiency is good.

  In the focus drive mechanism 400 configured as described above, the focus drive shaft 430 is rotationally driven by the focus motor 440. By this rotation of the focus drive shaft 430, the fourth lens group frame 104 (fourth lens group L4) is guided along the second optical axis OA2 by being guided by the focus guide mechanism 420. Thereby, the focus position in the imaging optical system changes. The rotation control of the focus motor 440 is performed by a control unit (not shown) of the camera 1.

According to the focus drive mechanism 400 as described above, the focus guide mechanism 420 also serves as the rotation stop guide bar 122 in the zoom drive mechanism 100 to guide the movement of the fourth lens group frame 104, so that high movement accuracy can be obtained. Moreover, since it can be rationally configured, the number of parts can be reduced.
Further, the assembly can be performed very easily by arranging the fourth lens group frame 104 in the frame 11 from the opened back side and then mounting the focus drive shaft 430.

As described above, this embodiment has the following effects.
(1) The lens barrel 10 can be moved and driven in conjunction with the first lens group L1 and the third lens group L3 by one zoom drive shaft 130 that is rotationally driven by one zoom motor 140. That is, the drive configuration can be simplified.

(2) In the lens barrel 10, a second lens group L2 that is an anti-vibration lens group is disposed between the first lens group L1 and the third lens group L3 that are relatively moved and zoomed. Thereby, a large blur correction amount can be obtained with a small movement amount of the second lens unit L2. As a result, it is possible to suppress degradation of optical performance due to blur correction.

(3) The lens barrel 10 is moved and driven in conjunction with the first lens unit L1 and the third lens unit L3 by one zoom drive shaft 130, so that the first lens unit L1 and the third lens unit L3 are driven. Can be linked with high accuracy.

(4) In the lens barrel 10, the first lens group L1 and the third lens group L3 are moved and guided by one zoom guide mechanism 120 (the zoom guide bar 121 and the rotation stop guide bar 122). For this reason, the position of both of the relative movement can be configured with high accuracy, and high optical performance can be obtained.

(5) In the lens barrel 10, the zoom motor 140 in the zoom drive mechanism 100 and the focus motor 440 in the focus drive mechanism 400 substantially vertically move the zoom drive shaft 130 in the zoom drive mechanism 100 on the same side of the frame 11. It is arrange | positioned so that it may pinch | interpose. Thereby, the zoom motor 140 and the focus motor 440 can be arranged extremely rationally, and the whole can be configured in a small size.

(6) The lens barrel 10 is zoomed from the second optical axis OA2 (center of the first and third lens units L1 and L3) to the axial center of the zoom guide bar 121: d1, and from the second optical axis OA2. The distance to the axis center of the drive shaft 130: d2 is set equal. With this setting, the distance between the zoom guide bar 121 and the zoom drive shaft 130 can be minimized, so that drive efficiency is good.

(7) The lens barrel 10 has a distance d3 from the second optical axis OA2 (center of the fourth lens unit L4) to the axis center of the focus guide bar 421, and an axis of the focus drive shaft 430 from the second optical axis OA2. The distance to the center: d4 is set equal. With this setting, the distance between the focus guide bar 421 and the focus drive shaft 430 can be minimized, so that drive efficiency is good.

(8) The lens barrel 10 opens the first lens group frame 101, the shutter unit 30, the shake correction mechanism unit 200, the third lens group frame 103, the fourth lens group frame 104, and the like inside the frame body 11. The assembly process can be performed from the back side, and assembly can be performed very easily.
(9) A first drive shaft (zoom drive) that drives the first lens group frame 101 and the third lens group frame 103 positioned before and after the second lens group frame 102 that moves in a plane perpendicular to the second optical axis. The third lens group frame 103 that fixes the third lens group L3 is positioned farther from the second optical axis than the second drive axis (focus drive axis 430) that drives the fourth lens group frame 104. Has a through-hole (through hole 103A) through which the second drive shaft (focus drive shaft 430) for driving the fourth lens group frame 104 passes, and the third lens group frame 103 and the fourth lens have a small configuration. A wide movement range of the lens group frame 104 can be ensured.

(Deformation)
The present invention is not limited to the above-described embodiment, and various modifications and changes as described below are possible, and these are also within the scope of the present invention.
(1) In the present embodiment, the first lens unit L1 and the third lens unit L3 are configured to be interlocked and driven by the zoom drive shaft 130 that is a cylindrical cam. However, the drive mechanism is not limited to this, and may be a plate cam or other means.

(2) In the present embodiment, the first lens unit L1 and the third lens unit L3 are interlocked. However, the arrangement of the optical system and the configuration of the interlocking lens unit are not limited to this example. For example, the first lens group and the second lens group may be linked.
In addition, although embodiment and a deformation | transformation form can also be used in combination as appropriate, detailed description is abbreviate | omitted. Further, the present invention is not limited to the embodiment described above.

  1: camera, 10: lens barrel, 11: frame body, 20: imaging optical system, 21: bending-introducing lens group, 21P: prism, 41: imaging device, 100: zoom drive mechanism, 120: zoom guide mechanism, 121: Zoom guide bar, 122: Anti-rotation guide bar, 130: Zoom drive shaft, 140: Zoom motor, 200: Blur correction mechanism unit, 400: Focus drive mechanism, 420: Focus guide mechanism, 421: Focus guide bar, 430 : Focus drive axis, 440: focus motor, L1: first lens group, L2: second lens group, L3: third lens group, L4: fourth lens group, OA1: first optical axis, OA2: second light axis

Claims (7)

In the lens barrel that bends the first optical axis to the second optical axis orthogonal to the first optical axis by the reflecting member,
A first lens group, a second lens group, a third lens group, and a fourth lens group, which are sequentially disposed along the second optical axis from the incident side;
A first actuator for moving the first lens group and the third lens group along the second optical axis;
A second actuator for moving the fourth lens group along the second optical axis;
A third actuator for moving the second lens group in a plane perpendicular to the second optical axis;
A first drive shaft disposed in parallel with the second optical axis and rotated by driving the first actuator;
A second drive shaft disposed in parallel with the second optical axis and rotated by driving of the second actuator;
A first lens group frame having an engaging portion that fixes the first lens group and moves along the first drive shaft;
A third lens group frame to affix said third lens group,
A fourth lens group frame having an engaging portion that fixes the fourth lens group and moves along the second drive shaft;
The first drive axis and the second drive axis are located on the same side with respect to a plane formed by the first optical axis and the second optical axis, and are orthogonal to the second optical axis. Some overlap in the direction,
The first drive shaft is located farther from the second optical axis than the second drive shaft;
The third lens group frame, said second drive shaft have a through portion that penetrates the engaging portion to move along the first drive shaft spaced apart from the second optical axis from the through portion Having
A lens barrel characterized by The lens barrel according to claim 1,
The first lens group frame and the third lens group frame move along the same first rectilinear guide shaft;
The first lens group frame and the third lens group frame are restricted from rotating about the optical axis by the same rotation stop shaft;
A lens barrel characterized by The lens barrel according to claim 2,
The first rectilinear guide shaft and the first drive shaft are disposed at an equal distance from the optical axis;
A lens barrel characterized by The lens barrel according to claim 3,
The rotation axes of the first actuator and the second actuator are parallel to the second optical axis, are arranged on the same side of the outer periphery of the lens group, and the first drive axis is parallel to the second optical axis. Arranged between the first actuator and the second actuator,
A lens barrel characterized by The lens barrel according to any one of claims 1 to 4, wherein
A second rectilinear guide shaft for guiding rectilinear advance of the fourth lens group frame,
The second drive shaft and the second rectilinear guide shaft are disposed at an equal distance from the optical axis;
A lens barrel characterized by The lens barrel according to any one of claims 1 to 5,
The first lens group frame, the third lens group frame, and the fourth lens group frame are restricted from rotating about the optical axis by the same rotation stop shaft;
A lens barrel characterized by   A camera provided with the lens barrel of any one of Claims 1-6.

Images